Unidentified Sentinel variant

This Unidentified Sentinel variant was an extremely large Sentinel-like machine used by the Forerunners during the Forerunner-Flood war.[1] It is the largest Sentinel variant observed to date, dwarfing the Strato-Sentinel in comparison. Its armament includes an extremely powerful energy weapon, capable of firing a lightning-fast energy beam at long range and producing an explosion powerful enough to level entire cities.[1]